Magnetic and optical tape media are frequently used for long-term storage of large quantities of data, such as in data backup or archive operations. Typical tape data storage and retrieval methods involve recording or writing data in tracks running length-wise down the tape, as well as retrieving or reading such data tracks from the tape. A multiple stripe head is used to write and/or read many parallel tracks. Magnetic heads may have more than 96 tracks with the ability to jog along the width of a magnetic tape to write and/or read more tracks. Optical tape data storage and retrieval systems using laser heads operate in a similar fashion.
The multiple stripe head designs mentioned above become inefficient as tape length is increased for greater capacity, such as in archive operations, because of the increased time it takes to access the data stored at the end of the tape. While shorter tapes result in quicker access time than longer tapes, shorter tape lengths also result in more limited storage capacity, thereby hindering archive operations where large data quantities are involved. A wide tape to boost capacity requires many more transducers in the head. Data throughput is also a factor of tape width and the number of heads. Limits to multiple stripe head designs include the number of read and write heads and overall tape width.
Problems arise in data recording when a large volume of data needs to be erased. In magnetic recording, this can be done through bulk erasure by a strong magnetic field. Magnetic recorders can also use a write operation for each data bit to ensure a random or blank pattern, although this can be time consuming. An optical recorder using phase-change media is not capable of bulk data erase methods, and a re-writing of random or blank bits would again be time consuming.
Performance of erasure methods in magnetic tape is also hindered by data security requirements, which may mandate a read-after erase cycle to verify erasure. Indeed, such requirements may go to extreme lengths to make sure data is removed. Repeated erase cycles may be required up to seven times to meet strict security standards. When data is written to a storage medium in bulk erasure methods, is necessary to read back the information in order to verify erasure by verifying data integrity. Typical optical recorders (DVD, etc) are not designed to perform this function, as the phase change media is not easily read back using a single laser element.
Thus, there exists a need for an improved tape media data storage system and method. Such a system and method would include a rotary head design, wherein multiple head elements available on a rotating head carriage assembly can be used to perform bulk data erasure. Existing write heads would be utilized in a read mode in order to do so without requiring additional dedicated read heads.